The invention relates to a steering wheel in accordance with the preamble of claim 1. Furthermore, the invention relates to a method of manufacturing such steering wheel. A steering wheel according to the preamble of claim 1 is known, for example, from U.S. Pat. No. 6,079,292 A.
Steering wheels known from practice substantially comprise a steering wheel skeleton encompassed by foam padding. In high-quality steering wheels it is moreover provided to add a wrapping to the team padding. Frequently leather or imitation leather is used as material for the wrapping. Due to the complicated geometry of a steering wheel the leather cannot be arranged at the steering wheel by an automated process. Rather, a complex and cost-intensive manual process is required to fix the leather on the steering wheel. For this purpose, usually appropriate leather cuts are provided which are laid around the foam padding until longitudinal edges of the leather cuts are adjacent to each other. The adjacent longitudinal edges then are manually stitched together. The connection of the longitudinal edges is carried out directly on the product which additionally impedes the stitching process. Hence leather-wrapping of a steering wheel is labor-intensive and time-consuming which in total results in high costs.
U.S. Pat. No. 6,079,292 A seeks to address this problem in that instead of stitching the longitudinal leather edges a profile bead for fixing the longitudinal rims of the leather by clamping in a groove of the foam padding. Concretely speaking, it is provided in the known steering wheel that the foam padding includes a groove directed inwardly to the central axis of the steering wheel into which the longitudinal edges of the wrapping leather are tucked. After that the profile bead is inserted between the longitudinal edges of the leather tucked into the groove. The profile bead is tucked into the groove of the foam padding, wherein the profile bead urges against the longitudinal edges of the leather projecting into the groove and thus forces them against the foam padding of the steering wheel. Concretely, this state of the art provides that the longitudinal edges of the leather are arranged to be clamped between the profile bead and the foam padding.
The clamping fixation of the leather in a groove of the foam padding known from the state of the art has drawbacks in practice. During use of the steering wheel frequently torsional forces are introduced into the leather wrapping. As a result the leather wrapping turns around the foam padding. In the area of the longitudinal edges of the leather wrapping tensional forces are acting which are capable of easily overcoming the clamping force of the profile bead. Thus the profile bead can easily detach and release the longitudinal ends of the leather wrapping. As a consequence, the leather wrapping detaches from the foam padding.